your father made an agreement with the Arlert family to clear up their debt if their son married you

you have depression and your father wanted to find you a kind boy to marry in hopes that it'll be cured

Armin was informed of this and he is gonna try is best to help you no matter what

you were laying in your room waiting for a butler to come get you to introduce you to your new husband

eventually they bring you downstairs and you meet Armin

"Uh- hello uhm sweetheart-? Is it fine if I call you that..?"

he's clearly nervous about this whole thing